Fascinating Fetal Finds

A 33-year-old G3P2 was referred to the Texas Fetal Center at 21 weeks and one day gestation with a placental mass diagnosed at 19 weeks and five days on her second trimester ultrasound. In addition to the mass there was an increased cardiothoracic ratio (CTR) but no additional abnormalities were seen. The mother was evaluated at the Center and showed a viable fetus with biometry that was appropriate for the gestational age. The fetus had an estimated fetal weight (EFW) of 377 grams and the amniotic fluid volume was normal. A large mass was seen on the surface of the placenta immediately adjacent to the placental cord insertion site. The mass measured a volume of 140 cc.

There appeared to be an artery/vein pair arising from the cord insertion site that provided multiple feeding vessels to the tumor (image 1). The fetal anatomic survey did not show any anomalies. The CTR measured 0.7 and the combined cardiac output measured 1,100 cc/kg/min. No evidence of hydrops was seen.

A diagnosis of placental chorioangioma was confirmed. After detailed discussion about management options, the patient elected to undergo an attempt to ablate the feeding vessels. On fetoscopic evaluation, it was possible to visualize the feeding vessels discrete from the remaining umbilical cord vessels. The patient underwent a combination of simultaneous laser ablation and bipolar coagulation of the vessels, and flow to the mass was completely obliterated (image 2).

The immediate postoperative course was uncomplicated and the pregnancy is ongoing.

About Chorioangioma

Chorioangioma is the most common placental tumor. Most are incidental findings on routine ultrasound and are small and of little clinical consequence. Large chorioangiomas measuring more than 5 cm in diameter are much less common and are often located near the site of the placental cord insertion. This is what limits options for therapeutic interventions.

Chorioangiomas have significant potential for both maternal and fetal complications. These include polyhydramnios, preterm labor, fetal anemia, cardiomegaly, intrauterine growth restriction (IUGR), hydrops and fetal demise. The presence of low resistance arterial-venous shunting within the mass can increase the demands on the fetal heart since blood flows preferentially along the path of low resistance. As the tumor grows it takes a greater portion of the cardiac output. The fetus increases its cardiac output to compensate while trying to maintain adequate perfusion of the rest of the fetus. Eventually the heart can no longer compensate. Cardiac failure develops and hydrops ensues. Therapeutic options are often limited and the prognosis, in the absence of treatment, is dismal.

Prenatal evaluation includes the size and location of the mass to determine if a prenatal intervention is possible. The cardiovascular impact of the tumor also needs to be carefully evaluated to determine if and when an intervention is performed. The team at the Texas Fetal Center is experienced in the evaluation and management of chorioangiomas and a variety of complex and unusual anomalies in pregnancy.

For more information about chorioangiomas or to schedule a consult, call (832) 325-7288 or toll-free at 1 (888) 818-4816.

Many physicians affiliated with Children’s Memorial Hermann Hospital are faculty at McGovern Medical School at UTHealth. The affiliated physicians from McGovern Medical School consults with patients at UT Physicians clinic with all advanced treatments provided at Children’s Memorial Hermann Hospital.